Sorry SCOTUS, if you don’t want to be perceived as partisan hacks, stop making decisions like partisan hacks
TL;DR
Some SCOTUS justices recently bemoaned the fact that the public views them as “partisan hacks” (in Justice Barrett’s words) and have rejected that view. Unfortunately for these SCOTUS justices, the data backs up the public’s view, not theirs.
The context
For example, here is an article explaining Justice Barrett’s position:
However, the data does not back up her view of things.
Going back to 2012, when I analyzed the Supreme Court’s decisions in the 2011 SCOTUS term, I wrote
It has been evident since 2000, after the Gore-Bush decision debacle, that the US Supreme Court is less a bastion of Constitutional Truth, and more a motley crew of partisans & ideologues, who were selected based on accidents of history regarding which justice died during whose administration, and who can and will put their ideology/party before any quest for Constitutional Truth.
The analysis in that post verified that point of view.
To see if the situation has changed in the past 10 years, I re-did the analysis, but this time using SCOTUS decisions from the 2020 term.
The data
Similarly to my earlier post, I calculated the percent of the times justices agreed on decisions with 6 or fewer concurring (i.e. 5–4 and 6–3 decisions).
Even though it’s been 10 years, the political landscape has changed, and the composition of the court has changed (Gorsuch, Kavanaugh, and Barrett
replaced Scalia, Ginsburg, and Kennedy), the political partisanship of SCOTUS decisions has remained mostly the same.
The conservative judges’ decisions are highly correlated, and the liberal judges’ decisions are also highly correlated. Kudos goes to Chief Justice Roberts for maintaining some level of correlation with the liberal justices.
The table above contains the same correlations, with the various clusters of judges highlighted.
- There are two top-level clusters, the ones shaded pink and blue, corresponding to the conservative and liberal judges.
- Within the blue (liberal) cluster we see agreement rates of ~90%-100%
- Within the pink (conservative) cluster we see agreement rates of ~50%-100%. This can be subdivided into two sub-clusters (red and orange), in which we see ~70%-100% agreement between the judges. These correspond to the more staunch conservatives (Alito, Thomas, Gorsuch) and the more moderate conservatives (Kavanaugh, Barrett, and Roberts)
- Roberts is the judge with the least imbalanced record.
Alternate view of the data
In addition to viewing the data in tabular form, like in the previous two tables, we can also visualize it in 3D. This way, the relationships between the various SCOTUS justices’ decisions can be more clearly seen.
I won’t go into technical detail into how this is done, but we can use the data in the above tables to embed the justices’ decisions into a 3-dimensional space. This is similar to what was done in research where N-dimensional embeddings were calculated for all words in the English language, which resulted in being able to visualize the relationships between the words (e.g. between king, queen, man, woman).
The above figure (which also appears at the top of this post), is the visualization of the data in the tables of the previous section, but “embedded” in 3D space, so we can more clearly see relationships between the justices.
It is now very clear that
- Kagan, Sotomayor, and Kagan are in a small cluster far away from the other judges.
- Within the umbrella cluster of the conservative judges, Barret, Kavanaugh, and Roberts form their own small sub-cluster, as do Thomas and Gorsuch. Alito seems like the lone conservative that is in a sub-cluster all by himself, and is the furthest away from the liberal cluster.
The GIF below shows the 3D visualization spinning, to get a better feeling of how the justices are clustered.
The bottom line
No matter how we look at the data, either in tabular form or using the 3D visualization approach, it’s clear that the SCOTUS Justices’ decisions are very clearly clustered along partisan lines.
Justices Barrett, Bryer, and others can bemoan the public’s perception of them as “partisan hacks” but until they change their decisions, the data speaks for itself.
Sources:
- Justice Amy Coney Barrett says Supreme Court is ‘not a bunch of partisan hacks’
- Stephen Breyer worries about Supreme Court’s public standing in current political era
- The US Supreme Court is useless
- 2020 term opinions of the Supreme Court of the United States
- Understanding Word Embedding Arithmetic: Why there’s no single answer to “King − Man + Woman = ?”
